Upper bound on the radii of regular ultra-compact star photonspheres

Abstract

We investigate the photonsphere in the background of regular asymptotically flat compact stars. The analysis includes the general hairy compact star considering the matter fields' backreaction on the metric in various gravity theories. We prove that the photonsphere of the compact star has an upper bound expressed in terms of the ADM mass of the spacetime. In the case of negative isotropic trace, a stronger upper bound can be obtained.

arXiv comment8 pages

References in corpus (46)

• Geodesic stability, Lyapunov exponents and quasinormal modes
• Light ring stability in ultra-compact objects
• Quasinormal-mode spectrum of Kerr black holes and its geometric interpretation
• Connection between black-hole quasinormal modes and lensing in the strong deflection limit
• Fundamental photon orbits: black hole shadows and spacetime instabilities
• Slowly Decaying Waves on Spherically Symmetric Spacetimes and an Instability of Ultracompact Neutron Stars
• Explosion and final state of an unstable Reissner-Nordstrom black hole
• Universal Bound on Dynamical Relaxation Times and Black-Hole Quasinormal Ringing
• Exotic Compact Objects and How to Quench their Ergoregion Instability
• The Quasinormal Mode Spectrum of a Kerr Black Hole in the Eikonal Limit
• Black-hole quasinormal resonances: Wave analysis versus a geometric-optics approximation
• Hairy Black Holes and Null Circular Geodesics
• Does the black hole shadow probe the event horizon geometry?
• Black holes have no short hair
• Unstable circular null geodesics of static spherically symmetric black holes, Regge poles and quasinormal frequencies
• Black hole solutions in Einstein-charged scalar field theory
• Stability of black holes in Einstein-charged scalar field theory in a cavity
• Upper bound on the radii of black-hole photonspheres
• General relativistic polytropes with a repulsive cosmological constant
• Spherical null geodesics of rotating Kerr black holes
• The fastest way to circle a black hole
• Resonance spectrum of near-extremal Kerr black holes in the eikonal limit
• Gravitational instability of polytropic spheres containing region of trapped null geodesics: a possible explanation of central supermassive black holes in galactic halos
• Resonance and absorption spectra of the Schwarzschild black hole for massive scalar perturbations: a complex angular momentum analysis
• A no-short scalar hair theorem for rotating Kerr black holes
• Black Hole Shadows and Invariant Phase Space Structures
• Scalar field configurations supported by charged compact reflecting stars in a curved spacetime
• No-hair theorems for a static and stationary reflecting star
• Charged massive scalar field configurations supported by a spherically symmetric charged reflecting shell
• On the thermodynamics of the black hole and hairy black hole transitions in the asymptotically flat spacetime with a box
• Self-gravitating field configurations: The role of the energy-momentum trace
• Photon spheres in Einstein and Einstein-Gauss-Bonnet theories and circular null geodesics in axially-symmetric spacetimes
• Charged reflecting stars supporting charged massive scalar field configurations
• Marginally bound resonances of charged massive scalar fields in the background of a charged reflecting shell
• On instabilities of scalar hairy regular compact reflecting stars
• Static scalar field condensation in regular asymptotically AdS reflecting star backgrounds
• The extreme orbital period in scalar hairy kerr black holes
• Hair mass bound in the black hole with nonzero cosmological constants
• Scalar field condensation behaviors around reflecting shells in Anti-de Sitter spacetimes
• Hair distributions in noncommutative Einstein-Born-Infeld black holes
• Lower bound on the compactness of isotropic ultra-compact objects
• Scalar condensation behaviors around regular Neuman reflecting stars
• Ultra-spinning exotic compact objects supporting static massless scalar field configurations
• Upper bound on the gravitational masses of stable spatially regular charged compact objects
• Hairy mass bound in the Einstein-Born-Infeld black hole
• Fermat's principle in black-hole spacetimes

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• The extreme orbital period in scalar hairy kerr black holes
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• The existence of null circular geodesics outside extremal spherically symmetric asymptotically flat hairy black holes
• Neutrino trapping in extremely compact Tolman VII spacetimes
• No-go theorem for static boson stars with negative cosmological constants
• Gravitational lensing inside and outside of a marginally unstable photon sphere in a general, static, spherically symmetric, and asymptotically-flat spacetime in strong deflection limits
• No scalar condensations outside reflecting stars with coupling terms from Ginzburg-Landau models
• A no-go theorem for scalar fields with couplings from Ginzburg-Landau models